Casing panel construction for heating appliance



May 21, 1968 A. M. cAsTELLo ETAI.

CASING PANEL CONSTRUCTION FOR HEATING APPLIANCE Filed Sept. 2, 1966 United States Patent O 3,384,069 CASNG PANEL CONSTRUCTION FOR HEATING APPLIANCE Anthony M. Castello and Robert R. Cooper, Wichita, Kans., assignors to The Coleman Company, Inc., Wichita, Kans., a corporation of Kansas Filed Sept. 2, 1966, Ser. No. 576,887 4 Claims. (Cl. 126-90) ABSTRACT GF THE DISCLOSURE A space heating appliance for location Within the room to be heated includes an exterior casing having at least one panel exposed to the room where the panel comprises in combination an outer panel member formed of thin sheet steel, an inner panel member formed of asbestos board, and a sheet of 'heat-reflective aluminum foil on the inner surface of the asbestos board. The outer surface of the asbestos board is adhesively attached to the inner surface of the steel sheet, and the aluminum foil is adhesively attached to the inner surface of the asbestos board. The steel sheet may range from .0l to .06 inch in thickness in combination with an asbestos board of thickness from 1,452 to :'/S of an inch. The panel construction is particularly adapted for wall heaters to provide a combination of sound deadening and heat insulation.

The outer casings or cabinets for heating app-liances such as wall heaters are ordinarily fabricated from light weight sheet metal such as sheet steel. Since the burner, combustion chamber, and heat exchanger operate in close proximity to the metal panels, the panels would become excessively heated if not insulated. The practice therefore has been to utilize conventional insulating material such as insulating matting formed from fiberglass, ceramic fibers, etc. While such expedients provide satisfactory insulation, they do not contribute any other desirable characteristics to the heater. In particular, it has been desired to provide wall heaters with sound dampening means. Not only is the sound of the operating burner and other internal noises, such as those caused by metal expansion or contraction, transmitted to the room through the casing walls, but the walls themselves can be a source of noise and discomfort. The light gauge metal forming the panels can be caused to vibrate and produce an unpleasant noise when it is accidentally struck or bumped with a solid object. While this may not occur with great frequency, it is still a problem which it has been desired to correct, and the noisy, tinny sound produced by striking the outside of the casing can be unpleasant and annoying to users of the heater.

It is therefore an object of the present invention to provide an improved panel construction for the exterior casing of a heating appliance which substantially overcomes the problems and difliculties described above. A related object is to provide an improved panel of the character described which not only overcomes the unpleasant sound and noise problems, but which also continues to provide satisfactory heat insulation. Still another object is to provide a panel construction of the character described which accomplishes the multiple functions of sound dampening and heat insulation without appreciably increasing the cost of the heater casing, and even in some embodiments achieving a decrease in cost. Further objects, advantages, and results will be indicated in the following specification.

Drawings This invention is shown in an illustrative embodiment in the accompanying drawing, in which- ICC FIGURE l is a perspective view of a heater casing sidi panel embodying the features of the present invention;

FIG. 2 is a side elevational sectional vieW of tht heater panel of FIG. l;

FIG. 3 is a perspective view of a heater employing sidi panels like those of FIGS. l and 2;

FIG. 4 is an enlarged fragmentary sectional view a: indicated at 4 on FIG. 2; and

FIG. 5 is an enlarged perspective view of a retaining clip which may be used with the panel construction.

Detailed description Looking iirst at FIG. 3, there is shown a space heate W having side panels S. The heater shown is a free stand ing gas-fired vertical room heater. Interiorly, it include a gas burner, a heater exchanger, a radiator, and a ut outlet. Since the construction of heaters of this genera type is well known in the art, it will not be further dis cussed herein.

Turning now to a description of the panel constructioi of this invention, reference is made particularly to FIGS l, 2, and 4. The casing panel S provides an outer pane member 1t) formed of sheet metal. In the illustratioi given, metal sheet 10 provides the exterior of the sidi panel of the casing. It will be understood, however, tha this invention may be applied to any or all panels of thi heater cabinet, including either or both side panels, th bottom panel, the front panel and the top panel, or por tions of the side, bottom, front, and top panels.

As indicated above, this invention is particularlj adapted for use with casing panel members formed o relatively light weight or thin gauge sheet metal. Whl sheet steel is preferred, other sheet metals can be usel such as aluminum. The invention is advantageous Wit` metal sheets having thickness of from .0l to .06 inch, bu usually the preferred thickness of the metal sheet wil range from about .018 to .047 inch.

To provide an improved appearance or for convenienc of assembly, the sheet metal casing member 10 can b formed integrally with right angle ange members, suci as the side and top flanges 11 and 12. The inner ends o these side anges may be provided with integral righ angle anges, such as the flanges 11a and 12a. It will b understood, however, that this invention is not limited t this particular means of fabricating a panel member.

In accordance 'with' the present invention, the casin panel is provided with an inner panel member 13 whicl is formed of asbestos board. As shown more clearly i FIGS. 2 and 4, the asbestos board member 13 is arranger with its -outer surface facing the inner surface of the shet metal member 10. As indicated at 14 the facing surface of the asbestos board and the sheet metal member are ac` hesively united. This provides a firm bond between th asbestos board 13 and the sheet metal member 10.

The asbestos board 13 can be, either asbestos millboar or rollboard. For the purpose of the present inventior these products are substantially identical in character, a though the rollboard is somewhat more flexible than th millboard, and is sold in rolls rather than in flat sheet: Both types of asbestos board are formed from asbesto fibers packed tightly together and united with a suit'abl fireproof adhesive such as sodium silicate. The asbestc board may contain a minor percentage of other tibrot material such as cellulose fiber. One commercial produ( which has been found particularly suitable is an asbestc millboard which can be described as a multi-laminar shet consisting of approximately asbestos combined wit cornstarch and cellulose liber, the sheet being produce on a cylinder paper machine, and sodium silicate bein used as the laminating adhesive. Such millboard sheet have entirely different heat insulating properties than ope fibrous mats of iiberglass, asbestos, or ceramic fibers. I

act, asbestos board, because of its density and continuous tructure, has relatively poor heat insulating properties, ,nd is not normally employed in applications where heat isulation is desired.

For the purpose of the present invention, the asbestos oard preferably has a thickness of about 1/15 to 1A inch Vith a 1A inch thick sheet being particularly suitable. Howyver, the present invention can be advantageously emloyed with somewhat thicker or thinner asbestos board, uch as asbestos board from about 1/32 to inch thickness.

The adhesive employed for bonding the asbestos board o the sheet metal is not particularly critical. Many adlesives are suitable, including epoxy resin adhesives, rubuer base adhesives, etc. For convenience of assembly, a emperature resistant contact cement can be used. Adlesives formed from synthetic rubber are particularly uitable. Commercial adhesives of this kind are sold by Iinnesota Mining and Manufacturing Company. In gen- :ral, any adhesives may be employed which are adapted or bonding iibrous material to metal, and which will not leteriorate under the ambient temperature conditions f a wall heater. The contact cement may be applied by )rush application to the inner surface of the metal sheet 1nd to the outer surface of the asbestos board 13. The urfaces may then be brought together. Certain desirable righ temperature type adhesives may be of the slow drying ype. To assist in retaining the asbestos board against the heet metal wall during the drying process, suitable clip etainers may be provided such as the lower clip and he upper clip 16 as shown more clearly in FIG. 2. Clip .5 is provided with an attachment portion 15a which may )e spot welded to the sheet metal wall 10, and with a bendtble tab portion 15b which can be folded upwardly over he lower edge of the asbestos board 13 after the adhesive las been applied. The clip 16 is insertable at the top of the lanel between flange 12a and the inner surface of the )oard 13. It includes spring tabs 16a and lob which esiliently hold it in place. After the adhesive-coated .sbestos board has been inserted, clip 16 may be snapped nto place to hold the upper edge of the asbestos board .gainst the sheet metal member 10.

To provide additional heat insulation, a sheet of heat `eiective metal foil is applied to extend over the inner urface of the asbestos board member. In the illustration given, the metal foil sheet is designated by the number 7, as shown more clearly in FIG. 4. Preferably the heat nsulating member 17 is formed from aluminum foil havng its bright or polished surface outwardly. There is no articular advantage in a thick layer of metal foil, and herefore the thinner metal foils `can be used, such as tluminum foils of .7 to 1 mil. More generally, aluminum r other reective metal foils of from .5 to 3 mils can be lsed. Usually, however, the preferred thickness will be less han 2 mils. The heat reflective metal foil may be ad'n lesively attached to the inner surface of the asbestos )oard 14 as indicated at 18 in FIG. 4. The adhesive may e of the same kind as used for joining the asbestos board o the metal wall.

The panel construction of the present invention proyides the desired sheet metal vibration dampening irn- )rovement without sacrificing insulating properties. The [eat insulation is comparable to that obtained by employng a foil-faced fiberglass insulating mat, which although :qually or more expensive, provides little or no sound lampening properties. The panel constructionv of the presnt invention is simple, economical, and provides a composite of desirable properties which have not heretofore been achieved in a sheet metal heater casing.

In the illustration given, the asbestos board 13 is shown extending for only about 2/3 of the height of the sheet metal member 10. If desired, however, the asbestos board 13 may be extended completely to the bottom of the panel. For the particular wall heater shown in FIG. 3, it has not been found necessary to extend the asbestos board for the full length of the panel. The objects of the present invention are satisfactorily accomplished with the construction shown.

While in the foregoing specification this invention has been described in relation to a specific preferred embodiment thereof and many details have been set forth for purposes of illustration, it will be apparent to those skilled in the art that the invention is susceptible to other em- Ibodiments and that certain of the details described herein can be varied considerably without departing from the basic principle of the invention.

We claim:

1. In a space heating appliance for location within the room to be heated and including an exterior casing having at least one panel exposed to said room, the construction of said panel comprising in combination:

(a) an outer panel member formed of sheet steel having a thickness of .Ol to .06 inch, said member comprising a portion of said exterior casing;

(b) an inner panel member formed of asbestos board having a thickness of from 1/32 to 3% inch,

said asbestos board member having its outer surface facing the inner surface of said sheet metal mem-ber and said facing surfaces being adhesively united; and

(c) a sheet of heat-reflective metal foil extending over and being adhesively attached to the inner surface of said asbestos board member.

2. The combination of claim 1 wherein said steel sheet has a thickness of from 0.18 to `0.47 inch.

3. The combination of claim 1 wherein said asbestos board has a thickness of from 1/16 to 1A inch.

4. In a wall heater including an exterior casing for mounting in the room to be heated, said casing having at least two side panels, each of said side panels comprising the combination of:

(a) an outer panel Imember formed of sheet steel having a thickness of from 0.18 to 0.47 inch, said member comprising a portion of said exterior casing;

(b) an inner panel mernber formed Of asbestos board having a thickness of 1&6 to 1A inch,

said asbestos board member having its outer surface facing the inner surface of said sheet metal member and said facing surfaces being adhesively united; and

(c) a sheet of aluminum foil having a thickness of .5

to 3 mils extending over and being adhesively attached to the inner surface of said asbestos board member.

References Cited UNITED STATES PATENTS 1,694,839 12/1928 Brooks 126-87 2,117,511 5/19-38 Scott 158-76 3,109,421 11/1963 Wilhoite 126-116 3,156,233 11/1964 OConnell 126--110 FREDERICK L. MAT'rEsoN, JR., Primary Examiner, E. G. FAVORS, Assistant Examiner, I

UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3,384,069

Anthony M. Castello et al.

May 2l, 1968 It is certified that error appears n the above identified patent and that said Letters Patent are hereby corrected as shown below:

Column 4, lines 38 and 46, "0.47", each occurrence, should read .047

Signed and sealed this 16th day of September 1969.

(SEAL) Attest:

WILLIAM E. SCHUYLER, IR.

Edward M. Fletcher, Jr.

Commissioner of Patents Attesting Officer 

